A steel catenary riser (SCR) attached to a floating platform at its upper end encounters fluctuations in and near its touchdown zone (TDZ), which causes the interaction with the seabed. Subsea surveys and the analysis of SCR’s indicated that the greatest stress and highest damage occurred near the touchdown point (TDP), where the SCR first touches the seabed. Nowadays, the linear seabed spring ...

In recent years, the production of oil and gas has been developed in deep water depths which exceed 500m. Deep water developments are being followed strongly in different parts of the world (Caspian Sea, Gulf of Mexico, etc.). The movement of floater causes severe stress at the touchdown point (TDP) in steel catenary risers (SCR). The main objective of this study was to simulate the exact behav...

We create a ’virtual-seabed’ platform to realize the 3D visual analysis of seabed on smartphone. The 3D seabed platform is based on a ’section-drilling’ model, implementing visualization and analysis of the integrated data of seabed on the 3D browser on smartphone. Some 3D visual analysis functions are developed. This work presents a thorough and interesting way of presenting seabed data on sma...

A class of RC-OTA hysteretic-chaotic generators has been proposed from the electronics point of view. Hysteresis is captured by an electronic realization. To extend its applicability, hysteretic mathematical modeling is an important issue. Here, a new hysteretic model is proposed. With this model, we realized a well known hysteretic-chaotic attractor using Simnon.

In this study, a coupled model is developed to address the dynamic response of an offshore pile to linear water waves. In the coupled model, the pile and the seabed are treated as a saturated poro-elastic medium described by Biot’s dynamic theory, while the seawater is considered as a conventional acoustic medium. To establish the coupled model, boundary element formulations for saturated porou...

Cold-formed steel (CFS) shear walls with concrete-filled rectangular steel tube (CFRST) columns as end studs can upgrade the performance of mid-rise CFS structures, such as the vertical bearing capacity, anti-overturning ability, shear strength, and fire resistance properties, thereby enhancing the safety of structures. A theoretical hysteretic model is established according to a previous exper...

In this paper, an efficient two-dimensional finite element model for a mooring cable and seabed interaction is built while geometric shape and tensions of the cable are computed in time domain. In the model, a hybrid beam element is employed to simulate the mooring cable with the seabed simulated by different soil constitutive models. When the elastic and elastic-plastic soil constitutive model...

The authors present a novel procedure for the automated rectification of side-scan sonar images. The traditional assumption of a flat seabed for the computation of the ground projection from the slant-range sonar data can later result in difficult geo-referencing and registration problems. Accurate rectification using actual seabed topography is required for precise integration of side-scan ima...

Based on theoretical analysis and experiments, this article proposes a new model for a magnetorheological (MR) damper. The proposed model with a smooth and concise form can interpret the bi-viscous and hysteretic behaviors of the MR damper very well. The parameters in the model have definite physical meanings. The bi-viscous and hysteretic behaviors can be characterized by two parameters 0 and ...